Best 2FA Authenticator App 2026: Aegis vs Google vs Authy (8 Compared)

Aegis has established itself as an open-source reference on Android, especially after Twilio removed the Authy Desktop client. This comparison is based on documented features, backup and encryption models, and the consensus of public reviews - not marketing screenshots.

New to the concept? Start with what a two-factor authentication app does.

Already using one and about to change handset? The backup model you pick here is what decides how the migration goes, and moving an authenticator app to a new phone covers the order to do it in.

This is exactly why SMS codes are risky - see SIM-swap attack protection.

Would you rather keep the codes inside your password manager than in a separate app? Tick "Built-in 2FA codes" in our password manager comparison: it keeps only the plans that really include them and prices each one over 1 to 3 years. Proton Pass fills them in its paid Pass Plus plan; section 09 explains the trade-off and why we still keep email and banking codes separate.

What is the best authenticator app in 2026?

2026 Podium:

1. Aegis - Android privacy champion. Local AES-256 vault, manual encrypted backups, GPL3 open source, zero cloud, zero tracking. Only downside: Android only.

2. Bitwarden Authenticator - Best choice if you already use Bitwarden as your password manager. Open source, E2EE sync, iOS + Android. Two separate apps, same ecosystem.

3. Google Authenticator - Best mainstream choice. iOS + Android, E2EE sync to Google Account (since 2023), 600 million users, minimalist interface. Closed source.

4. Microsoft Authenticator - Essential in the Microsoft/Azure ecosystem. Push notifications, passwordless, Microsoft cloud backup.

5. Authy - Still functional in 2026 (mobile) but no longer recommended for new users. Desktop removed August 2024.

Quick recommendation: Android privacy-first → Aegis. iOS or mainstream → Google Authenticator or Bitwarden Auth. Microsoft enterprise → Microsoft Authenticator. Codes on phone and computer → Proton Authenticator (section 09).

What is a TOTP 2FA app?

An authenticator app is a form of two-factor authentication (2FA) - the "something you have" second factor. TOTP = Time-based One-Time Password, defined in RFC 6238 (2011). The protocol generates a 6-digit code valid for exactly 30 seconds, calculated from two elements:

• A secret key (160-bit seed, shared during 2FA activation, encoded in the QR code)
• The current Unix time rounded to 30 seconds

The calculation is a local HMAC-SHA1 - no internet connection required to generate the code. The server and your app perform the same calculation; if the codes match, you're authenticated.

2FA Method Security Comparison:

TOTP is 10x more resistant to SIM-swapping than SMS. Learn more about passkeys vs passwords to go further up the security hierarchy.

How do the main authenticator apps compare?

All apps are completely free - no premium tier for the authenticator itself.

None of these five has a desktop app. If you want your codes on a Windows, Mac or Linux computer as well, see Proton Authenticator in section 09.

04 - Profile of Each App

Aegis Authenticator

Launched: 2018. Maintainer: beemdevelopment (open source community). Platform: Android only (F-Droid + Google Play).

Strengths: The most robust vault in this comparison. AES-256 encrypted at rest. JSON import/export with encryption. Automatic backup to local folder or Android cloud (Drive, Syncthing, etc.) but fully user-controlled. Clean interface, dark mode, fast search, custom groups.

Weaknesses: Zero iOS. Zero native automatic sync (manual configuration required). For non-technical users, the backup setup can be intimidating.

Target user: Privacy-maxxers, advanced Android users, journalists, security researchers, anyone wanting zero-trust toward the cloud.

Bitwarden Authenticator

Launched: 2023 (separate app from the password manager). Platform: iOS + Android.

Strengths: E2EE sync via Bitwarden account. Open source like Bitwarden (GPL3). If you already use Bitwarden as your password manager, integration is natural. Clean interface, import from Google Authenticator and Authy.

Weaknesses: Requires a Bitwarden account (free, but cloud dependency). Still a young app (fewer advanced features than Aegis). Will never merge with the main Bitwarden app (deliberate company decision for risk separation).

Target user: Existing Bitwarden users. People wanting open source + multi-device sync without friction.

Google Authenticator

Launched: 2010. Users: 600 million+. Platform: iOS + Android.

Key 2023 evolution: Google added automatic TOTP code sync to the Google Account (E2EE optional since April 2024). Before 2023, no native backup - losing your phone meant losing your codes. This change solved the app's main weakness.

Strengths: Simplest app to use. Native Google ecosystem integration. 600M+ users = near-universal compatibility. E2EE sync available.

Weaknesses: Closed source. Google Account dependency. Limited code export (Google protobuf format, not standard TOTP). If you lose your Google account, you lose your TOTP codes.

Target user: Mainstream users. Google ecosystem users. People who don't want to configure anything.

Authy (Twilio)

Launched: 2012. Acquired by Twilio 2015. Platform: iOS + Android (Desktop removed August 2024).

What changed: Twilio officially retired the Authy Desktop apps (Windows, macOS, Linux) in August 2024, citing a desire to focus on mobile. Desktop users lost access - a major blow for power users. The mobile app remains functional.

Strengths: Mature mobile multi-device. Cloud backup AES-256 encrypted with separate backup password. Clean interface.

Weaknesses: Closed source. Desktop removed. Twilio is a B2B telecom company, not a security-first company. History: 2022 phone number leak (33 million users). Not recommended for new users.

Target user: Existing users who don't want to migrate. New users should prefer Aegis or Bitwarden Auth.

Microsoft Authenticator

Launched: 2016. Platform: iOS + Android.

Strengths: Native Azure AD / Microsoft 365 integration. Push notifications for 1-tap approval. Passwordless mode (sign in without password via notification). Cloud backup tied to Microsoft account.

Weaknesses: Closed source. Microsoft Account dependency. Heavier interface than alternatives. TOTP code export impossible (data locked in Microsoft ecosystem).

Target user: Azure AD companies. Microsoft 365 users. Enterprise MFA context - see our enterprise password manager guide.

Aegis vs Google Authenticator: the direct answer

This is the pairing most people are actually deciding between, so here it is head-to-head rather than buried in a table.

Google Authenticator wins on one thing that matters more than enthusiasts admit: it is already there. It is available on both Android and iOS, it needs no configuration, and it now syncs codes to your Google account so a lost phone is no longer a catastrophe. The trade-offs are the ones you would expect from a closed product: the code is not auditable, your seeds sit with the same company that holds your email, and there is no app-level lock or encrypted local export in the way an open-source tool provides.

Aegis wins on control. It is open source and auditable, stores its vault encrypted locally, and gives you a real export you own, which makes leaving it as easy as arriving. It also offers app-level locking (PIN or biometric) so someone holding your unlocked phone still cannot read your codes. The decisive limitation is platform: Aegis is Android-only. On iOS it is simply not an option.

How to choose, honestly:

• On iOS, the comparison ends before it starts: Aegis is unavailable, so the real choice is between Google Authenticator and another cross-platform app.
• On Android, if you want auditable code and an encrypted local vault you control, Aegis is the stronger choice, and its export makes the switch reversible.
• If you value zero setup and automatic recovery on a lost phone over auditability, Google Authenticator is a defensible choice rather than a mistake. Its sync solved the single biggest reason people used to lose access to their accounts.

One point that applies whichever you pick: the app is not the weak link, the backup is. An authenticator with no recovery path is how people get locked out. Section 06 below covers migrating from Google Authenticator to Aegis step by step if you decide to move, and our full Aegis vs Google Authenticator comparison sets out who holds the secrets and where each app is ahead.

Authy vs Aegis: the direct answer

The other pairing people arrive with, and the two apps are almost mirror images of each other.

Authy wins on reach and recovery. It runs on both Android and iOS, which already puts it somewhere Aegis cannot go, and its encrypted cloud backup means a drowned phone is an inconvenience rather than a lockout. That backup is the whole proposition: your seeds are stored with Twilio, encrypted with a password you set, and restored by logging back in.

Aegis wins on ownership. Open source and auditable, vault encrypted on the device, real export in a format you keep, app-level PIN or biometric lock. Nothing of yours sits on anyone's server. Its two limits are exactly Authy's strengths: Android only, and no cloud recovery, if you lose the phone and the backup you made yourself, the codes are gone.

How to choose, honestly:

• If any of your devices is an iPhone or iPad, Authy is the workable answer and Aegis is not an option at all.
• If everything you own runs Android and you want no third party holding your seeds, Aegis is the stronger choice, provided you actually export the vault somewhere safe.
• If you would not reliably make your own backups, Authy's cloud recovery is worth more to you than auditability. An unrecoverable vault protects your codes from you as effectively as from an attacker.

Worth knowing before you commit either way: Authy retired its desktop applications in 2024, so "runs everywhere" now means mobile plus browser access rather than the native desktop app people remember. And Aegis's export is what makes it a safe place to start: leaving is a file copy, not a migration. The full Aegis vs Authy comparison covers where the secrets live and what it takes to leave Authy.

Which authenticator app encrypts your backups?

Risk #1: Cloud compromise

If the cloud server is compromised, what happens?

• Aegis: zero cloud risk (no cloud). Vault stored locally, AES-256 encrypted even if you manually copy the file to Drive.
• Bitwarden Auth: Bitwarden cloud stores client-encrypted data. Bitwarden completed a Cure53 audit in 2023. Zero plaintext server-side.
• Google Auth: Google stores your TOTP seeds in your Google account with optional E2EE. If someone accesses your Google account → risk.
• Authy: Twilio servers + separate AES-256 backup password. The decryption key never leaves your device if the backup password is strong.
• Microsoft Auth: Microsoft cloud storage. If your Microsoft account is compromised → risk.

Risk #2: Central account stolen

Google Authenticator and Microsoft Authenticator create a single point of failure: if your Google/Microsoft account is compromised, the attacker can access your TOTP codes AND your email AND your other services simultaneously.

Golden rule: use a 2FA app that's separate from your primary email provider. If you use Gmail, don't use Google Authenticator for critical accounts.

Risk #3: Export and portability

For migration: Aegis (encrypted JSON, trivial) > Bitwarden Auth (JSON export) > Authy (difficult, no direct export) > Microsoft Auth (impossible natively) > Google Auth (Google protobuf format, requires the app to scan).

Portability matters for long-term security: being locked into an ecosystem = risk of losing access on platform change.

Risk #4: the app is not the whole defence. Whichever app you pick, a TOTP code can be relayed in real time by a phishing page, or sidestepped entirely by a stolen session cookie, neither is fixed by choosing a better app. How attackers bypass MFA, and what stops them covers those attacks and the settings that actually blunt them.

How do you move from Authy or Google Authenticator to Aegis?

Authy Desktop disappeared in 2024 - if you were a Desktop user, here's how to migrate to Aegis cleanly.

Prerequisites: Aegis installed on Android + Authy on mobile.

Method 1: Re-scan QR codes (clean but slow)

1. For each service, go to Settings → Security → 2FA
2. Disable existing 2FA (enter Authy code to confirm)
3. Re-enable 2FA - a QR code appears
4. Scan with Aegis
5. Confirm the Aegis code works

Method 2: Via Authy Desktop (if you still have access) The Authy Desktop app, before its removal, allowed seed export via a community script. This method is no longer available for new users (Desktop removed).

Google Authenticator → Aegis migration (official method):

1. Google Authenticator → Menu → Transfer accounts → Export accounts → Select all
2. Transfer QR code generated (Google protobuf format)
3. Aegis → + → Scan → Import from Google Authenticator
4. Scan the QR with Aegis
5. Do not delete Google Authenticator until you've tested Aegis on 2-3 critical sites

After migration: immediately enable Aegis encrypted backup (Settings → Backups → enable auto-backup + set a strong backup password).

Which authenticator app should you use?

Maximum security wanted (Android) → Aegis. Local encrypted vault, zero cloud, open source, manual encrypted backups. Slightly more complex initial setup, but zero compromise on privacy.

Already using Bitwarden → Bitwarden Authenticator. Integration is natural. Open source, E2EE sync. Our Proton Pass vs Bitwarden comparison can help validate your primary manager choice.

Mainstream user, iOS or Android → Google Authenticator. Easiest to configure, E2EE sync available, 600M+ users. Closed source but acceptable for standard use.

Enterprise with Azure AD / Microsoft 365 → Microsoft Authenticator. Push notifications, passwordless, native integration. For enterprise MFA context, see our enterprise password manager guide.

Already using Authy and it works → stay for now, but plan a migration to Aegis or Bitwarden Auth medium-term. The Authy ecosystem has stagnated since the Desktop removal.

Want the codes next to your passwords, in one app → Proton Pass Plus. Its built-in authenticator fills the 6-digit code right after the password (section 09 explains the trade-off and why we keep banking and email codes separate). The free plan is enough to test the manager itself first.

08 - Two More Open-Source Picks: 2FAS and Ente Auth

If you want open source but Aegis's Android-only, offline-first model doesn't fit, two cross-platform options are worth knowing.

2FAS is an open-source TOTP app for iOS and Android. It keeps secrets on the device, offers optional encrypted backup to your own iCloud/Google Drive, and ships a browser extension that lets you approve codes from the desktop without re-syncing seeds to a server. It's a strong pick if you want open source on iOS specifically, where Aegis isn't available.

Ente Auth is the open-source authenticator from the team behind the Ente photos app. It adds end-to-end encrypted cloud sync across devices (iOS, Android, desktop and web) on top of standard TOTP, with import from Google Authenticator, Aegis and 2FAS. It suits people who want Aegis-style openness plus automatic multi-device sync without tying their seeds to a Google or Microsoft account.

Both are free and open source. For Android-only offline use Aegis still leads; for cross-platform open source, 2FAS (device-local + optional backup) and Ente Auth (E2EE sync) are the two to compare.

Key reminder: TOTP 2FA is a security layer on top of your password manager. Both are complementary - a strong unique password + TOTP = optimal protection.

For definitions of TOTP, HOTP, 2FA, passkey and hardware key, see the PwdFortress authentication glossary.

09 - Proton Authenticator, and codes inside your password manager

Proton Authenticator is the newest app in this guide and fills the one gap the main table leaves open: the desktop. Facts below are from Proton's product page, checked on 18 October 2026.

• Price: free on every platform, no ads, no tracking.
• Platforms: iPhone, iPad, Apple Watch, Android, macOS, Windows and Linux.
• Account: none required. No email, no phone number. A Proton account is only needed if you want sync between devices, and that sync is end-to-end encrypted.
• Import: from Google Authenticator, 2FAS, Aegis, Bitwarden Authenticator, Ente Auth and LastPass Authenticator. Authy is not on the list, so Authy users still have to re-scan their QR codes (section 06).
• Export: yes, so leaving is as easy as arriving.
• Open source: yes, like all Proton apps.

Who it suits: people who want the same codes on a phone and a computer without handing them to Google or Microsoft. On Android-only setups where you want zero cloud, Aegis keeps the edge; Proton Authenticator is the open-source answer when you also use a desktop.

Should your 2FA codes live inside your password manager?

Several password managers can store the TOTP secret next to the login and fill the 6-digit code for you. Proton Pass does it in its paid plan (Pass Plus, 2.99 USD a month billed 35.88 USD a year, checked on proton.me on 18 October 2026; the built-in authenticator is not in the free plan).

The honest trade-off:

• For: one app instead of two, the code is filled automatically, and an autofill that only works on the real domain also helps against look-alike phishing pages.
• Against: password and second factor sit in the same vault. If the vault is opened (stolen master password plus an unlocked device), both factors fall together. That is why we keep a separate authenticator, or a hardware key, for email and banking, and use built-in codes for everything else.

If that split suits you, Proton Pass is the manager we would pair with Proton Authenticator: same company, same end-to-end encryption model, and you can start on the free plan before deciding whether the built-in codes are worth paying for. If you are still weighing it up, our is Proton Pass safe review covers its encryption, audits and free plan limits.

PwdFortress reviews security apps independently, based on public documentation and feature analysis. No standalone 2FA app in this comparison pays a commission. The Proton Pass links in this article are affiliate links: if you subscribe through it we may earn a commission, at no extra cost to you. Proton Authenticator itself is free and earns us nothing. Internal links to Bitwarden are editorial: Bitwarden has no affiliate programme and pays us nothing.

Related guides

• Security Key vs Authenticator App: What NIST Actually Says About Phishing
• What Are Backup Codes? The List You Clicked Past, and Where It Should Actually Live
• Aegis vs Google Authenticator: Local Encrypted Vault or Google Account Sync?
• Aegis vs Authy: Encrypted Local Vault or Cloud Sync Across Devices?
• Aegis vs Bitwarden Authenticator: Encrypted Vault or Plain Local Storage Synced With Your Vault?